The West Atchafalaya Floodway is a flood control structure of the Mississippi River and Tributaries Project located in the Lower Atchafalaya Basin

Atchafalaya Basin

The Atchafalaya Basin, or Atchafalaya Swamp, is the largest swamp in the United States. Located in south central Louisiana, it is a combination of wetlands and river delta area where the Atchafalaya River and the Gulf of Mexico converge. The river stretches from near Simmesport in the north...

 in south-central Louisiana

Louisiana

Louisiana is a state located in the southern region of the United States of America. Its capital is Baton Rouge and largest city is New Orleans. Louisiana is the only state in the U.S. with political subdivisions termed parishes, which are local governments equivalent to counties...

. It has a project design flood

Project design flood

The project design flood is a hypothetical "maximum probable" flood of the Mississippi River used by the United States Army Corps of Engineers to aid in the design and execution of flood protection in the Mississippi Valley....

 flow capacity of 250000 cuft/s.

Atchafalaya Basin floodways

The Atchafalaya Basin system comprises three floodways. Two of these, the West Atchafalaya Floodway and the Morganza Floodway, are at the northern end. Together with the Atchafalaya River

Atchafalaya River

The Atchafalaya River is a distributary of the Mississippi River and Red River in south central Louisiana in the United States. It flows south, just west of the Mississippi River....

, these floodways are designed to pass flood waters into the third component, the Lower Atchafalaya Basin Floodway, which is 833000 acres (3,371 km²) in size and is bounded on the north by U.S. Route 190

U.S. Route 190

U.S. Route 190, also known as the Ronald Reagan Memorial Highway, is an east–west United States highway in Louisiana and Texas. It evolved from the shortest of intrastate routes in 1926 to a length comparable to a main Interstate Highway route, leading from the swamps and pine forests of...

, on the east and west by the Atchafalaya Basin protection levees, and on the south by the Gulf of Mexico. Farther downstream, floodwaters enter the Gulf of Mexico

Gulf of Mexico

The Gulf of Mexico is a partially landlocked ocean basin largely surrounded by the North American continent and the island of Cuba. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on the southeast by Cuba. In...

 through the Atchafalaya River below Morgan City, Louisiana

Morgan City, Louisiana

Morgan City is a city in St. Martin and St. Mary parishes in the U.S. state of Louisiana. The population was 12,404 at the 2010 census....

 and the Wax Lake Outlet.

See also

• Mississippi River floods
  Mississippi River floods
  The Mississippi River and its tributaries have flooded on numerous occasions. This is a list of major floods.-Flood of March 1543:Hernando DeSoto's party was passing through a village at the confluence of the Mississippi River and Arkansas River on March 18...
  
  
• Bonnet Carré Spillway
  Bonnet Carré Spillway
  The Bonnet Carré Spillway is a flood control operation in the Lower Mississippi Valley. Located in St. Charles Parish, Louisiana - about west of New Orleans - it allows floodwaters from the Mississippi River to flow into Lake Pontchartrain and thence into the Gulf of Mexico...
  
  
• Old River Control Structure
  Old River Control Structure
  The Old River Control Structure is a floodgate system located in a branch of the Mississippi River in central Louisiana. It regulates the flow of water leaving the Mississippi into the Atchafalaya River, thereby preventing the Mississippi river from changing course. Completed in 1963, the...